Kaiming Liang^a, Xuhua Zhong^a,⁎,
Nongrong Huang^a, Rubenito M. Lampayan^b,c, Yanzhuo Liu^a,
Junfeng Pan^a, Bilin Peng^a, Xiangyu Hu^a,
Youqiang Fu^a

Science
of The Total Environment

doi.org/10.1016/j.scitotenv.2017.07.118

Abstract

 Nitrogen
non-point pollution and greenhouse gas (GHG) emission are major challenges in
rice production. This study examined options for both economic and
environmental sustainability through optimizing water and N management. Field
experiments were conducted to examine the crop yields, N use efficiency (NUE),
greenhouse gas emissions, N losses under different N and water management.
There were four treatments: zero N input with farmer's water management (N0),
farmer's N and water management (FP), optimized N management with farmer's
water management (OPT N ) and optimized N management with alternate wetting and
drying irrigation (OPT N +AWD). Grain yields in OPT N and OPT N +AWD treatments
increased by 13.0-17.3% compared with FP. Ammonia volatilization (AV) was the
primary pathway for N loss for all treatments and accounted for over 50% of the
total losses. N losses mainly occurred before mid-tillering. N losses through
AV, leaching and surface runoff in OPT N were reduced by 18.9-51.6% compared
with FP. OPT N +AWD further reduced N losses from surface runoff and leaching
by 39.1% and 6.2% in early rice season, and by 46.7% and 23.5% in late rice
season, respectively, compared with OPT N . The CH 4 emissions in OPT N +AWD
were 20.4-45.4% lower than in OPT N and FP. Total global warming potential of
CH 4 and N 2 O was the lowest in OPT N +AWD. On-farm comparison confirmed that
N loss through runoff in OPT N +AWD was reduced by over 40% as compared with
FP. OPT N and OPT N +AWD significantly increased grain yield by 6.7-13.9%.
These results indicated that optimizing water and N management can be a simple
and effective approach for enhancing yield with reduced environmental
footprints. 

附件：Nitrogen losses and greenhouse gas emissions under different N and water management in a subtropical double-season rice cropping system